The Maw is a endlessly growing blob of semi-transparent purple goo, that grows depending on how much it eats. The Maw is said to have a an intelligence that is lower developed than a puppy. The purple blob is controlled by Frank, who is the alien that the player controls in the game, The Maw. The Maw is a creature similar to Kirby since they both have the power of absorbing the powers or characteristics of things that they absorb. For example, when it eats Yums (small pink blob-like creatures) the Maw grows in size, or when it eats the fiery Gastros, The Maw also gains the ability to breathe fire.
The Maw also makes a Cameo appearance in Twisted Pixel's 2nd Title "'Splosion Man" where the Maw is sucked out into space.